(a) To allow rectifier aging and film formation, it is considered good practice to use 1.5 as a
E = 1.5 x 32.7 = 49.1 V.
(b) The rectifier chosen should produce a d.c. voltage that meets the size requirements of 60-volt,
(8) Locate the rectifier adjacent to tank for the following reasons:
(a) Usually cheaper to install.
(b) Easier to maintain.
(c) Keeps d.c. voltage drop to a minimum.
(9) The d.c. circuit conductors should be installed as follows:
(a) Outside tank -- use No.2 AWG high molecular weight polyethylene extruded (HMWPE)
(b) Inside tank -- use No.8 AWG HMWPE conductor.
(10) The cable should not be stressed or bent.
Elevated water tank (ice is expected).
Impressed current cathodic protection is designed for an elevated water tank as shown in figure D-5. The
tank is already built and current requirement tests have been done. Anodes must not be suspended from the
tank roof because heavy ice (up to 2 feet thick) covers the water surface during winter. The anode cables
could not tolerate this weight, so another type of support must be used. Button anodes must be mounted on
the tank's floor and lightweight platinized titanium anodes must be suspended in the riser from the tank